• The Korean Journal of Pain
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• 제14권2호
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• pp.199-206
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• 2001

Background: The lumbar sympathetic ganglia are variable in both position and numbers. The aim of this study was to detect the appropriate lumbar vertebral level where the lumbar sympathetic ganglia primarily aggregate. Methods: Forty patients comprising of hyperhidrosis (26 cases), complex regional pain syndrome (10 cases), peripheral artery occlusion disease (3 cases) and postherpetic neuralgia (1 case) underwent lumbar sympathetic block. We randomly selected one of two (L2 or L3) levels and the L4 level. The position of the needle tip and distribution of dye was verified by injection of a mixture of radio-opaque dye (1.5 ml) and 4% lidocaine (1.5 ml) and subsequently confirmed by L-spine anteroposterior and a lateral view X-ray. We considered the response positive when the skin temperature increased more than $1^{\circ}C$ in 5 min. Results: In general, the positive response ratio was greater when the needle tip located at the L2 or L4 level vice L3 and when the drug was distributed on the lower half of the L4 body and in the L4/5 intervertebral disc space. In a right side block, the positive response ratio was greater when the drug was distributed on the lower half of the L4 body and in the L4/5 intervertebral disc space, although in a left side block there was no significant difference seen between the levels. The complications of the neurolytic block were alcohol neuritis (7.5%) and hypoesthesia (5%) on the L1 or L2 dermatome. Conclusions: The best effect with least chance of complication may be induced by spreading the drug on the lower half of the L4 body and/or into the L4/5 intervertebral disc space by placing the needle tip on the L4 body.

• 한국멀티미디어학회논문지
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• 제8권10호
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• pp.1347-1359
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• 2005

본 논문에서는 공간 명암도 의존 행렬을 이용하여 문서영상의 다양한 블록들을 상세하게 분류해 낼 수 있는 방법을 제안하였다. 제안한 블록분류 방법에서는 먼저 명암도 문서영상을 이진화하여 평활화 기법을 적용함으로써 명암도 영상의 질감특징을 이용하여 분할하는 것보다 신속하게 블록을 분할하고 동시에 그 위치정보도 구할 수 있도록 하였다. 분할된 각 블록들의 공간 명암도 의존 행렬로부터 문서블록들의 7가지 질감특징을 구하고, 이를 정규화한 다음 역전파 신경회로망를 이용하여 문서블록들을 분류하였다. 문서블록들을 큰 문자, 중간 문자, 작은 문자, 표, 그래픽 및 사진 등 여섯 가지 유형으로 상세 분류하였다. 또한 명암도 문서영상의 2차 통계 질감특징을 얻기 위해 공간 명암도 의존 행렬을 구할 때, 기존의 사진과 같은 일반 영상분할에서와는 달리, 문서블록 고유의 특징이 잘 반영되도록 하였다. 즉, 분할된 각 블록을 하나의 마스크로 정하여 수평 한 방향의 공간 명암도 의존 행렬을 구함으로써 고속의 질감특징추출과 상세 블록분류가 가능하도록 하였다.

• 전자공학회논문지S
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• 제34S권4호
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• pp.25-32
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• 1997

In this paper, we propose an adaptive BTC algorithm using the characteristics of the error signals. The BTC algorithm has a avantage that it is low computational complexity, but a disadvantage that it produces the ragged edges in the reconstructed images for th esloping regions beause of coding the input with 2-level signals. Firstly, proposed methods classify the input into low, medium, and high activity blocks based on the variance of th einput. Using 1-level quantizer for low activity block, 2-level for medium, and 4-level for high, it is adaptive methods that reduce bit rates and the inherent quantization noises in the 2-level quantizer. Also, in case of processing high activity block, we propose a new quantization level allocation algorithm using the characteristics of the error signals between the original signals and the reconstructed signals used by 2-level quantizer, in oder that reduce bit rates superior to the conventional 4-level quantizer. Especially, considering the characteristics of input block, we reduce the bit rates without incurrng the visual noises.

• 한국멀티미디어학회논문지
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• 제6권2호
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• pp.259-266
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• 2003

본 논문에서는 블록 내의 움직임 정도에 따라 다단계의 블록 레벨을 설정하고, 각 블록 레벨에 따라 각기 다른 움직임 예측을 수행하는 다단계 움직임 예측 알고리즘을 제안한다. 이는 움직임이 없거나 적은 영역에서의 잉여 탐색 과정을 제거하여 계산적 효율성을 증대하고, 움직임 정도가 큰 영역에 대해서는 움직임 예측 과정을 심화시켜 예측의 정확성을 향상시킨다. 실험결과 프레임 당 적은 수의 블록으로 고정된 크기의 블록을 가진 전역 탐색 블록 정합 알고리즘과 Three-Step 탐색 알고리즘보다 MSE를 20% 정도 감소시켰으며 연산량은 전역 탐색 블록 정합 알고리즘과 비교하여 98%, Three-Step 탐색 알고리즘과 비교하여 56% 정도 절감하는 효과를 얼을 수 있었다.

• 한국환경복원기술학회지
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• 제7권6호
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• pp.19-28
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• 2004

Segmental Retaining Wall(SRW) has been variously applying in Civil and Architecture construction. Recently, the application of environmental element in all type's structures came to essential requirement, and the construction cases of retaining wall using reinforced soil and block are more increased than the past. But, this trend more widely was spread environmental element as landscape work for the backside of reinforced retaining wall as well as block itself. New environmental block, Greenstone Block, developed to apply of this tendency. The retaining wall system using Greenstone can be environmental constructing at both block itself and backside of retaining wall. The material tests, the axial compressive strength test of block and bending test of fiber-pipe, exercised to design and construction of vertical SRW, which were satisfied NCMA standard. Through this procedure, Rewall (ver 1.0) was developed, which can be automation design of SRW including internal stability, external stability and local stability. And these can be considered setback of retaining wall, as well the examples of vertical retaining wall using block presented to satisfying the follows; strength of reinforced geotextile, height of retaining wall, surcharge, types of backfill and groundwater level etc. Many problems investigated on after or before of construction were due to local failure, insufficiency of bearing capacity and groundwater level. Especially, the local failure was many occurred to during compaction or after construction, and the cases of SRW construction is similar to the results of model test on vertical SRW.

• International Journal of Internet, Broadcasting and Communication
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• 제6권2호
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• pp.10-12
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• 2014

This work is based on the motion estimation to handle the ill-posed nature. The algorithm used in this study that performs the motion estimation for overlapped block is used to calculate with using pixel of neighborhood block with higher correlation and present block by considering the correlation level of neighborhood block. The proposed method shows in a significant improvement in the quality of the mothion field when comparing the conventional methods.

• 디지털산업정보학회논문지
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• 제5권4호
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• pp.179-187
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• 2009

In this paper, an efficient multi-level successive elimination algorithm using the locality in block was proposed for motion estimation. If SAD(sum of absolute difference) is calculated from large absolute difference values to small absolute difference values, SAD is increased rapidly. So, partial distortion elimination in SAD calculation can be done very early. Hence, the computations of SAD calculation can be reduced. In this paper, an efficient algorithm to calculate SAD from large absolute difference values to small absolute difference values by using the locality in block. Experimental results show that the proposed algorithm is an efficient algorithm with 100% motion estimation accuracy for the motion estimation of motion vectors.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.938-941
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• 1995

This paper is concerned with the determination of assembly unit for hull block assembly processes for shipbuilding. In this study,genetic algorithm is adopted for assembly level allocation and assemaly unit is determined by rule-based reasoning. The criteria to detemine assembly unit is to minimize welding operation time for the block assembly.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(1)
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• pp.73-76
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• 2000

In tendency of digitalization, we studied about the purpose of digital modem for MRI spectrometer and advantage of digital modem compared with analog one. We introduce requirements lot designing transmitter of high speed digital modem for MRl spectrometer We also introduce its top-level and mid-level architecture. The transmitter is composed of CPC-P interface block, DUC & DAC block, RF block, master clock generation block, MCU block. Especially, DUC and its control parts are studied in detail. DUC and DAC can operate up to 52MHz and 100Msps, respectively. However we uses 35MHz as master clock and this paper shows its validity through simulations.

• 한국컴퓨터산업학회논문지
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• 제5권1호
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• pp.147-156
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• 2004

본 논문에서는 블록 합 피라미드 알고리즘에 기초한 빠른 움직임 추정 알고리즘을 제안하였다. Efficient Multi-level Successive Elimination Algorithm의 Spiral Diamond Mesh Search 기법과 Partial Distortion Elimination 기법을 개선하여 이들을 블록 합 피라미드 알고리즘에 적용하였다. 제안된 알고리즘의 움직임 추정 정확도는 거의 100%이고 블록 합 피라미드 알고리즘의 연산량을 효과적으로 줄였다. 실험을 통하여 제안된 알고리즘의 효율성을 확인하였다.